The purpose of this project is to provide consultative services in statistical and epidemiological methodology in the design, interpretation, and evaluation of clinical trials of diagnosis and treatment of cancer and other studies requiring this kind of expertise. For some trials, the Section provides full statistical support, including development of detailed study plans, assistance in the design of appropriate study forms, supervision of randomization and collection, processing, and editing of data, performance of interim analyses during the progress of the study, preparation of progress reports, final analysis of study data, and collaboration in the preparation of scientific papers. During the past year the Section has continued to provide full statistical support for the randomized clinical trials conducted by the Lung Cancer Study Group, the Brain Tumor Cooperative Group, and the Intergroup Study of Testicular Cancer. In the area of diagnosis, the Section is responsible for maintaining an up-to-date inventory and clinical data for a large serum bank containing information and sera for some 1,500 women with breast cancer, 3,000 women with benign breast disease, and 6,300 asymptomatic controls. Other diagnosis-related projects include a clinical trial of the Makari skin test and evaluation of multiple markers for diagnosis of lung cancer. Other major collaborative work has included a prospective, longitudinal examination of hospice care for terminal cancer patients, a controlled assessment of the psychological impact of breast cancer, and an analysis of prognostic factors for malignant melanoma using SEER data.